Influenza vaccine response in community-dwelling German prefrail and frail individuals

Jürgen M Bauer,Karine Vidal,Celine Romagny,Rebecca Diekmann,Jalil Benyacoub,Antonio De Castro,Nabil Bosco

doi:10.1186/s12979-017-0098-z

Abstract

BackgroundThe age-related dysregulation of the immune system in older persons results in reduced responses to vaccination and greater susceptibility to infection, especially in frail individuals who suffer the greatest of morbidity and mortality due to infection. Recently, significantly reduced anti-influenza antibody titers and increased rates of influenza infection after vaccination were reported in community-dwelling American frail older adults. The aim of our study was to further assess the relative impact of frailty and of each individual Fried frailty criterion on influenza vaccine response. Prefrail and frail community-dwelling German persons aged ≥70 years were recruited for a nutritional randomized double-blind placebo-controlled clinical trial conducted during the 2014–2015 influenza season. Herein, we present a sub-analysis study of the placebo group to compare 76 prefrail and frail participants.ResultsPrevious seasonal influenza vaccination rate was relatively high (77.6%) in the 76 volunteers aged from 70 to 93 years. Of these participants, 65.8% were diagnosed as prefrail and 34.2% as frail according to the Fried frailty criteria. In both prefrail and frail groups, elevated levels of pre-vaccination seroprotection were observed to all vaccine strains (H1N1: 54% and 32%, H3N2: 60% and 72%, B: 10% and 16%). Post-vaccination, similar increases in haemagglutination-inhibiting antibody titers were observed for the three vaccine strains in both prefrail and frail groups. No significant difference in geometric mean titer (GMT) ratios and in rates of seroconversion or seroprotection were observed between prefrail and frail groups. Regarding the five Fried frailty criteria, only participants with low physical activity had significantly lower GMT to the strains H3N2 (55.4 vs 103.7, p = 0.001) and B (13.9 vs 20.0, p = 0.06), as compared to those having normal physical activity.ConclusionsInfluenza vaccine response was not significantly affected by the frail phenotype, as defined by Fried frailty criteria, in community-dwelling German individuals. However, low physical activity may be a relevant predictor of lower serological response in vaccinated older individuals.Trial registrationClinicaltrials.govNCT02262091 (October 8, 2013).

Highlights

The age-related dysregulation of the immune system in older persons results in reduced responses to vaccination and greater susceptibility to infection, especially in frail individuals who suffer the greatest of morbidity and mortality due to infection
Mosterin Hopping et al suggest that the ageassociated decline in antibody responses may be an effect of repeated annual influenza vaccination rather than age [8]
Subjects scoring positive for the “low physical activity” criterion had significant lower geometric mean titer (GMT) against the H3N2 and the B strains when compared to those who were negative for this criterion (H3N2: 55.4 vs. 103.7; p = 0.001, B: 13.9 vs. 20.0; p = 0.06, respectively). Summarizing the above, these results suggest that among the five frailty criteria, the “low physical activity” criterion showed the strongest association with a diminished serological response after influenza vaccination in prefrail and frail individuals

Summary

Introduction

The age-related dysregulation of the immune system in older persons results in reduced responses to vaccination and greater susceptibility to infection, especially in frail individuals who suffer the greatest of morbidity and mortality due to infection. Significantly reduced anti-influenza antibody titers and increased rates of influenza infection after vaccination were reported in community-dwelling American frail older adults. Prefrail and frail community-dwelling German persons aged ≥70 years were recruited for a nutritional randomized double-blind placebo-controlled clinical trial conducted during the 2014–2015 influenza season. Diminished specific antibody responses observed in older persons may increase the risk of infections and thereby limit the effectiveness of vaccines (i.e. percentage reduction of disease in a vaccinated group of people compared to an unvaccinated group) with fluctuating rates which can drop from 50% to 11% depending on the clinical settings, the vaccine formulation and the circulating virus strains [12, 13]. Influenza associated morbidity and mortality remain a major public health challenge in western societies and they may further increase as a consequence of the demographic change we are facing with the population above 60 expected to double in size by 2050 [14]

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